1. Field of the Invention
The present invention relates to a film information reading device for a camera and, more particularly, it relates to a film information reading device arranged to read an information pattern concerning a film formed on an outside peripheral surface of a film cartridge containing said film.
2. Description of the Related Art
As shown in FIG. 5, a film cartridge 1 has an information pattern 2 on its outside peripheral surface.
In order to read such information pattern, two types of film information reading devices have been heretofore employed. One of them includes one contact member per one pattern, while the other includes two contact members per one pattern.
The usual information pattern formed on the film cartridge is constructed to indicate the information by detecting a conductive or non-conductive state of the pattern relative to a standard pattern. However, where the film information reading device is of the one contact member per one pattern type, it is difficult to effect reliable detection of the conductive or non-conductive state, owing to the unstable condition of the surface of the information pattern and, consequently, it is difficult to perform precise reading of the information.
For the reasons described above, the device of the one contact member per one pattern type lacks reliability in reading of information. The device of the two contact members per one pattern type has been proposed, with the object of improving the reliability in information reading and such a device is disclosed, for example, in U.S. Pat. No. 4,582,408 or U.S. Pat. Ser. No. 783,847. However, the device of the two contact members per one pattern type requires two independent contact mechanisms, so that efficiency of assembling it is low and manufacturing cost is high. Furthermore, in the device including two independent contact members, there is a limitation in the pitch of the contact members and there is also the danger of the contact member coming into contact with an incorrect pattern portion, owing to an accidental shifting of the film cartridge.
In the conventional construction of the film information reading device, the contact member in the form of a cap is movably supported and energized by an electrically conductive spring, which contacts, at its opposite ends, with the contact member and a pattern portion of a flexible printed circuit board, respectively. In such a conventional construction, direct contact is formed between the end of the contact member and the pattern portion of the flexible printed circuit board, so that there is a danger that the contact member may damage the pattern portion of the flexible printed circuit board.